Dry ore-separator.



W. W. BGNSON.

:om ons summon.

APPLICATION ILED 00T. 27. 190B.

Patented Jan. 3, 1911.

lil l b I w1 lilllii.. l .HHIINMHHI I oo o 'F1 is Glxhtueooe W. W.BONSON.

DRY OBB SEPABATOR.

LPPLIGATION 111mm om. sv. 190s.

980,89TLs 'UNITED STATES PATENT OFFICE.

WILLIAM W. BONSON, OF DUBUGUE, IOWA, ASSIGNOR TO BONSON DRY'CONCENTRATOR .CO., OF DUBUQUE, IOWA, A CORPORATION OF ARIZONA.TERRITORY.

DRY cnn-SEPARATori.

Patented Jan. 3, 1911.

Application tiled October 27, 1909. Serial No. 524,975.

ters Patent of the UnitedStates were granted and issued to lVilli-am lV.Bronson and iVillson L. McLaughlin on the 7th day of September. 1909,'and vnumbered 933,053.

'In what it consists, its manner of con'-v struction, mode of operationand in what particulars it is ditlierentiated' from the aforesaidmachine will be fully explained -in 'the following specification andclaims v and illustrated in the drawings accompany- .ing the same andmade apart hereof.

Figure 1 is a side elevation of the jig table and moth` of supportingit. Fig. 2 1s a perspective view of Fig. 1 wit-h part cntl away showingthe construction ofthe sustaining grate bars. Fig. 3 is a head endelevation of the jig and supporters, Fig. 4 is aperspective view of avportion of the table showing the gates and a part cut away showing themethod of operating same, and the ore concentrating bed with theretarders thereon. Fig. is a plan viewl of one of the girdcrs that carrythe gates, and a plan viewv of a portion of the ore detiectors. Figp isa side view7 of Fig. 5. Fig. 7 is a section on line w-rv of Fig. "4.Fig. 8 is, a sectional view on line fz/-g/ of Fig. 9. Fig. 9 is a planview of the table. J

Like characters of reference denote corresponding parts in cach of thedrawings.

Referrinor to the drawings 2 designates the jig which consists oigatable 4, beneath which is an air box 5 and 'pivotally mounted onstandards 6. Tlie'standargls are formed into rings or cups 10-1t theirtops, which form bearings for thelanlesfl -to which the jig is attachedThe lower end ofthe standards are similarly `-formed and are pivotedupon the shaft. 1G which have their bearings 18 rigidly secured upon thefoundation 20.

In order to provide for the inclination.

lengthwise of the jig the standards at the foot are set on thefoundations 20 at clifferentheights and this inclination may be variedby raising or lowering either foundation, whereby it is adjusted to therequired height to adapt it to different conditions of the massv to beseparated thereon. It is often desirable to have the table also inclinesidewise or laterally,jand a convenient mode if making such inclinationis given by inserting a wedge 22 between the axle 12 and the bottom ofthe jig 2. This inclination may be varied by the different thicknessesot' wedgesor in any convenient way to also adjust the j igfordiil'erent. conditions of the mass to be separated.

To the frontend ofthe jig is coupled a shaft 26 which is connected withthe power whereby the jig is given a short reciprocating motion. Themeans -Whereby it is reciproeated may bethe saine' as set out in theaforesaid patent, but any other mode may be used.V It isvintended toimpart to the jig a reciprocating motion kupward in the arc of a circle,and as the jig is .reciprocat'edonly a short distance it will have atrembling or shaking motionwhereby with the air thatx is. forced throughthe mass to be separated, such mass will be immediately stratified.

' The table which is secured on the top of -the air box 5 is preferablyformed ot cast metal having the' side bars 27 and grate bars QS. lt isimportant, onv account 'otI what is placed over and upon this grate,that these bars 28 should be accurately made and that they should beexceedingly rigid and therefore. they are cast and then the barsmachined. Upon this grate is stretched a mesh 30 preferably of finetextile fabric which extends over the upper surface of the grate andthrough which a current of air forced. Against the under side of thegrate in the air chamber there may also be stretched a coarse mesh 31through which the air is delivered to the mesh 30 by a more evendistribution, but this4 is not. a necessity only under certainconditions of the mass, usually when the mass is reduced to a linepowder. air for aiding in the separation of the ore is 'introduced intothe air box in the base ot the jig through a flexible pipe'SZ which isconnected with a blower in substantially the .sa-mc manner as in theabove mentioned application, and since any other convenient The serilwrlheroin.

38 of the table leavinglja space 4 0fibe Ween 135 vlt is of r `uneimoortance that these oi'e des -Underneath these gir ers 44, 45 nnd'fltlthe .detlectors 35 ure;groovcd or cut through or Inode muy he used it isnot niiuutely de- Upon the inesh El() nre secured ore deflecors 35.which nre set parallel to each other and above und parallel to thegrate bars 28 und et. nn angle to the length et' theta'ble le-eters besel" parallel Withand rest upon und hc of prscticully the saine width asthe grate hors, not only to provide for the stability et" the table andprotect. the mesh but also te prevent any interference of the nir upnr-tween the grate bars through the mesh.

Upon the ore dcfiectors 35 ure secured girngue dr-tlectors 15G that areset et an anglev to. the dette-eters und also at nn :ingle to the lengtht the jig. -n order that there may be grr :igidity to the tableandnnitorinity in the runways V'both for the; ore und gungue, und alsomore accurately peral- ,lel the ore detlectors 35'With the'grate bars'28. the delico-tors 35 and 36 are preferably cust together andmachined.'

The detlectors 3G on thetir'sdivisiofof the tnblemny' bedispensedjxvith'qand still there would be a separationofthe orebut. notas fast, :is the detlectors fserve to 'force the gangne fromoif theore'nafterjftheinss' has been stratifiedby the actionfof'v theair andmotionof the jig.' The deliecto'rs 3l :ire preferably cut ott at one endtoward t 'dei the ends of the'fdeicctorsand thefside the table asa'runway for ythe'gangue thatis separated fromjthe ore onthisffdivisfion Longitudinzilly ofl thegtablefffnd'e little `to onesideof the centernresecured tothe endf of the table, beams "or girders,r44,45

and 46 which rest upon the ore delectors-SS. Theunder edges of thesegirdersare .pro-- vided with agroove 48 and with vertical openings 50.lIn the grooves 48there is ady y justably secured gates 51, 52 and-53.To these gates are secured pins 55. which :ire 'adapted to project upthrough the opening 50 in the gir-ders, and are provided with screwthreads near their tops. .For the pur` pose of adjusting these gutestodifferent.; l heights, thereare provided keepers'-5ft-Tsecured to theupperedgeof the girdershy the' screws 58, and in these'keepers arelocatednuts tl() which ae'ndapted to en nge'fthcj threaded end ofthe.pins ,55 .and a just the gutes vertically in the rooves of thegirders.V

nearly through substantially the sume width :as the width of the gates,so that the 'gates may be adjusted vertically down to or nearly to themesh. There may be one or more of the gates according tothe kind nudclassifi-A cationof orc to be separated. In the drn'- ings Ihnve shownthree secured parallel to would be suflicient. It is not a necessit thatthese. gates run exactly lengthwise t i l the bed but should be set atan angle to the deflectors and substantially dividing the tablelengthwise. Between these gates therel is no necessity for the ganguedetlectors 3G and hence none are shown, though they may extend throughthis spacebetween the gates. These gates serve to divide the table onwhich the largest part of the gangue is seported from the ore from theside on which is formed the concentrating ore bed from the bottom ofwhich the ore 1s constantly' drawn olf while the ore is delivered on topof the bed from the other side of the division of the table.

The division of the table substantially lengthwise gives an enormouslcapacity to the machine, The mass is stratified almost immediately onbeing 4delivered onto the table, the gangue suspended by the action of-the'air and aided by the motion and pitch Hoff-the table, is'forcedbythe'gangue de- 'flctors at a 'great rate of speedy into the runway onone divisionzof the table and down the end ofthe table' -'at-1f'.. The.ore travels muchg'more'slowly as'the' air pressure Vis not strongenoughto suspend it and its movement, is governed raeticallyby the throwandpiteh of the ta 1e. Thefriction of such y `a largefmountioffgangue issulicient to ectoi's'on-the gangue side-ofthe divisionv of thel table..Theffirst" gate is therefore left suliciently high that allv thev ore,the middlings' and necessarily some of thegangue wilL ass under it. TheAsucceeding ggites V are a justed so as to allhvvn free passage of theore and yet retar'theiovv of vthe, gangue sol that'ity will rise` 'abovethe ore deectors and be carried down between' the gates over the end ofthe tabled?, B and C; v

One of the@essential d'terences' between this `51p licationgandlthebefore mentioned patent 1s k'the""Sii'btn tially longitudinal di'-vision of the table andthe means for form'- ing andin'aintainingfan oreconcentrating bed, which has been found hy experiment to be. ofle'xcecding importance 1n the purity of the separationof ores,A eseeially where the mass-to be se arated has in it various kinds ,of'o'res of 'di cient-specific gravity. Along the,outerfvlongitudinaledge of the'table is 'secured another .girder 62 similarly supplied`with n'groove inits'lower longitudinal edge inwvhiehfis set anothergate 64, a d npted to be adjusted onto thelmesh and form with the e'mesh a tightxjoint.- This gate is adjusted vertically in the samemanner. as the other gates.' Between" the gate 53 andthe outer 'gate 64'is located the concentrating bed G5. The onx f aztle'ctors 35 arecontinued over the iso table at this division and help to provide meansAfor forming the ore bed. Over the ore detlectorsare set at au anglethereto and at an angle to the length of the bed, retarders (33 whichpreferably extend from the girder (Si). about two-thirds across the oreconcentrating hed and are set at a ditt'erent angle to the detlectors 35from that of the detiectors 3G.

The detiectors :Bti hasten or crowd the separation b v forcing thegangue from ott' the ore on the other division ot' the table, but theretarders (i8 aid in forming the ore concentrating bed by retardingtheore and gangue upon the bed until there has been a completeconcentiption of the ore and all'of the pure or heaviest values havesettled and are ready t-o be drawn off'fron'i the bottom of the bed fromunder the gate (34.

The ore bed could not be vformed on the gangue side of the division of-the table as the ore is passing too rapidly down between 'the oredcfiectors and too large a bod)y of gangue isA passing over the saine sothat they friction would carry with it the ore into the gangue.Therefore, to form the ore concentrating bed the ore and. thegangue.left must travel vat a much slowerrate of speed than it travels whenstratified from the gangue at its delivery onto-the table.

`Along the side of the air box 5 and beneath the gate .(34 is a chute 67for collecting' and disposing of the ore as it ls deliv` ered frombeneath the gate (S4.

At 'the front end above the table is a hopper 66 which extends acrosslthe table to near the first gate and through which the mass to beseparated is delivered along the head of the table.

The manner of operating my device is suhstantially as follows. The massto be separated is first surface dried and classified then deliveredthrough the hopper Gt along the,`

head of thevfii'jst division ofthe table amid the deitectors 35 and 3Gand at thcanie time the air is turned on into theair box 5 through thepipe 32 whereby it isforced up .through the mesh and through the mass.

At the same time the table is given a reciprocating motion which takenwith the air immediately stratifies` the massraising the gangue to thetopand leaving the ore between the deflectors 35, and asthe table isinclined both longitudinally and laterally -the largest-part. ofthegangue will be forced hv the gangue detiec'tors 36 toward the side ofthe table and through the runway over hc tops of the-deflec'tors 35 andoff at the end A of the table. This will dispose of most oftine/ganglio.l out. the ore; the middlings and spine of the gangue willbe carried under the.

ga'te 51.

Tliegates 5'1. 52 and 53 have previously been 4adjusted in such a`mannerthat; lthe gate 51` is nearlyto the top of the orc detieetors 35, thegate 52 down at about half of the width of the detiectors -35 and thegate53 a slight distance lower down. As the ore and middlings togetherwith someof the gangue pass in the runways between the ore detiectors 35under the gate 5l between the gates 51 and where there are no ganguedetlectors the middlings and some of the gangue will pass down and bedelivered over the end of the table atI B. The or'e will then pass onunder the gate 5'2 and some more of the gangue and middlings will be`delivered over the foot of the table between the gates 52 .and 53 at-C, and the ores of ditferent values together with the middlings and someof the gangue will pass under the gate 53 and be delivered to form theore concentrating bed, then the second division of the table by itsconstruction including the retarders (i8 and the important space betweenthe ends of the retarders and the gate 53. will rapidly dispose of thegreatly reduced and com-entrated mass thereon and send the remaininggangue and middlings ott from the cone ntrating bed around the ends ofthe retarders into the space and down off from the vend of the'table atH. while'the concentrated lore will be drawn otffrom the bottom of thebed under the gate 64 as fast. as it is .delivered uponthe concentratingbed. It will bef seen that though the separation is e.\feeedinglyrapid'after the concentrating 'bed is once formed 'still the purity ofthe separation will always he preserved as long as the concentrating bedis maintained. At -this -time in order to form a concentrating bed ofore which is the great essential in the perfect separation of ore, thegate 64 is adjusted down to., the mesh and will not allow anything topass beneath it. .and some of the middlings are delivered upon thisl bedfrom underneath the gate into the spacel'ietween the gates 53 and G4their movementl will be arrested by the 'gate't-l and retarded by theretarders G8 andI will soon be'tlled nearly` to the top 0f thedefleetors and with certain lrinds of ore to near the top of theretardcrs 68. Since the retarders tits" retard. the movementof the4 massand especially of the gangue A.and other lighter particles thatl arestratified on top of the pure ores. in a short time the oreconcentrating bed will be formed,'comp0sed of the heavier ores likegold, silver and copper at the bottom with those of lighter specificgravity above and on top the middlings and gangue. Then theconcentrating bed is fullvformed thenv the operator raises the `gatet4 ashort distance sufficient to allow the ore to pass out from beneath thisgate into the chute 65 and the gangue and middlings that'are on theSurface of the ore bed will gradually pass around the ends of theretarders through ,the space and be delivered over the end of the tableat H. The opera- Then the ore tor then watches the ore bed and variesthev i esoei height ofthe gate G4 until it will deliver the pure ore.into the chute as fast as it is delivered upon the bed from beneath thegate 53 and thus carefully maintain the bed'of ore amid the deflectors35 and retarders 68.

It will be seen that it is exceedingly nec essa ry for the pureseparation vof the ore that the ore bed 'ne formed and maintained atapredetermined depth according to the kind and quality of the ore to beseparated, and at a place on the table where the ore is practically freefrom gangue so that the -friction of a small amount of gangue. passingover the ore will carry with it but very little if any ore over the endof the table. Vhen the ore concentrating bed has been formed theheaviest particles of the concentrates will be always at the bottom ofthe ore bed,

and the middlin s together with whatever angue is still le t will remainon top or be elivered over the end H of the table.

It will be seen that it is ofthe utmost importance that the constructionof the ma# chine between the gates 53 and 64 shall be such that 'theoperator can arrest and retard the movement lof lthemassand thus form anore concentrating.; bed of the desired thickness according tothe,various kindsofores in the mass to be se rated-fand thenl mainvtairiithat concentrating b edwhile the ore of vthe highest valufes isdrawnoi ,from the bottoni of the concentrating bed as fastaas 'it' isdelivered thereon and further all the gangue and lighter product will.be carried out around the ends of the retarders and delivered overthetail ofthe machine at-'I-I.

Having now described my invention what I claim and desire to secure byLett-ers Patent is:- t"

1. In la. dry ore Separator, a table provided with a mesh, 'means forimparting motion to the table, means for forcing air through the mesh,means for dividing the table vvlonvitudinally, means for forcing thegangue rom 'off the -stratified mass on one sideof the dithe table, oredeflectors set on the mesh atan angle to the length of the table,-gangue de- 'fiectors set upon the ore deectors at au fing-le theretoand at an angle to the length ot the.

table, an adjustable gate set lengthwise of the table dividing thetable, means comprising an adjustable gate for forming an oreconcentrating bed on one divisionj of the table, and means forlmaintaining Isaid ore l bed at a given depth while the ore is drawn ofi'from thle bottom of the bed beneath the gate. Y

3. In a.' dry ore separator, a table, a mesh upon the table, means forforcing a constant current or" air through the mesh, means for impartingmotion to the table, a gate set sub stantially lengthwise of the tabledividing the table, means for ormingnn orc concentrating bed on one sideof the table consisting of ore delectorS, retarders, and a gate at theend of the ore detiectors adapted to be adjusted to aid in forming thebed and to draw off the ores of heaviest values from the bottom of thebed while. the partially separated oie lis delivered from underneaththegiisional gate upon the o're concentrating 4. In a dry ore sepaiiator, atable provided with a mesh, means for forcing air through the table,means for imparting motion to the table, means .for dividing the Atablein substantially a longitudinal manner, means for removingl part of thegangue from one division oft e table, and means'including diagona'llydisposedV detlectors set upon the table with. retarders u on thedeflectors at an abigletheretm an a gate onone side of the forl formin'an ore concentrating bed upon the other (Ii-vision of the tableand for-.ms'iintainin said bed.

. In a ore separator, a table, a mesh upon ,the tab e, means for forcingair throu h the mesh, means for imparting motion to t e table, anadjustable gate for dividing the table substantially lengthwise, meansfor rej moving part of the gangue from one division ofthe table, andmeans for forming an ore concentrating bed upon the other division ofthe` table.

6. In a di'v ore separator, a'table, a mesh upon the table, means forforcing air through the mesh, means for imparting motion to the table, agate for dividing the table substantially lengthwise, means foradjusting the gate upward and downward, means for partially removing thegangue from olf the 'ore on o ne side .of .the gate and means forforming an ore concentrating bed on the other division of the table byarresting the move-l ment of the mass upon the mesh over a constantcurrent of air. t

7; In a dry ore. separator, a table provided .with a mesh, means forforcing a constant dividing the table-lengthwise consisting of a girder1provided Ywith a groove and agate adapte( tobe adjusted in the groovein the girder, means for removing part of the angue from ott the ore onone side of the division, and means for forming an ore concentrating bedon the other division of the table. 8. In a dry ore separator, a tableprovided with a mesh, means for forcing a constant current of airthrough the mesh, means for imparting motion to the table, meansfordividing .the table substantially lengthwise consisting of a girderprovided with a groove lengthwise therein-and vertical openingstherethrough, a gate. provided with arms adapted to engage the openingsin the girders, means attached t0 the arms for adjust-A ing the gate inthe groove in the girder, means for removing part of the gangue .fromoft the ore on one division of the table,

and means for forming an ore concentrating bed on the other division ofthe table.

9. In a dry ore separator, a table, a mesh upon the table, means forimparting motion to the table, a gate dividing the table Substantiallylengthwise, means for formin an ore concentrating bed on one division othe table by arresting the movement of lthe mass and means forretardingthe movement o the mass forming the ore bed while it is subject to aconstant current of air up through the mass. y

10. In a dry orc separator, a table, a mesh upon the table, means forimparting motion to the table, means for forcing a currentof air throughthe table, a ate dividing' the. table substantially longit-u inally,means including detlectors upon the mesh and re# tarders on thedeiiectors at an angle thereto for forming an ore concentrating bed uponone division of the tahle, means including a gate upon the outer side ofthe ore concentrating bed-for arresting the movement of the mass whileit is subject to the ressure of air therethrough until the bed is ormed.

11. In a' dry ore separator, a table provided with a mesh, means torimparting motion to the, tahlc, means for forcing air through the table,a gate dividing the table in substantially a longitudinal plane. meansfor forming an ore concentrating bed on one division of thetableconsisting of ore deiectors and a gate along th'l ends of the oredetlectors adapted to be, adjusted to stay the movement of the 'massuntil the concentrating bed is fully formed.

12. In a dry ore separator', .a table provided with a mesh thereon,means for in iparting motion to the table, means for forcing ay constantcurrent of air through the table, agate dividing the table substantiallyin a longitudinal manner, and means for forming and maintaining an oreconcentrating bed on one division of the table consistingof lleectorsset at an angle to the length of the table etarders on the oredelict-tors at an angle therto together with an adjustable gate, setalongr the ends of the ore detlcrtors and rctarders.

13. In a dry orf.l separator, a table, la mesh upon the table, oredeflectors diagonally disposed 'on ine mesh, ganguc deflectors set uponthe ore detiectors at an angle thereto and at an angle to the length ofthe table. means for forcing a constant current of air through the mesh,means for imparting motion to the table, a gate upon the derlectors atan angle` thereto and dividing the table substantially lengthwise, andmeans for forming an ore concentrating bed consisting of an adjustablegate set along the ends of the ore defiectors and retarders sev curedupon the ore detiectors and extending part of the way between the gatesfor retarding the movement of the mass on the ore hed 'and directingvthe gangue into the space ends of the retardrs -while the ore is drawnoff from the bottom of the bed beneath the outer gate.

14. In a dry ore separator, a table pro-` vided with a mesh, means forforcing a c onstant current of` air through themeslnmeans for impartingmotion to the table, means for partially separating the 'greaterpartici` the gangne from the ore on one side of the table, a. pluralityof gates adapted to be adjusted t'o near the mesh on the table topartially arrest the speed of,` the movement of the mass and divide thetable substantially lengthwise under which the 'partially separatedmassis vdelivered to the opposite side of the table, andf means inclut ng a.gate adapted to be4 adjusted to the mesh 'on the table and set at theend of the ore detiectors for forming and maintaining an oreconcentrating bed from the partlally separa-ted ore as it is deliveredfrom one division of the table under the dividing gates upon theconcentrating bed.

15. In a dry ore separator, a table provided with a mesh, means forforcing a constant current of air through the mesh, diagonally disposedow. deflectors on the mesh,

means for imparting a reciprocating motion on the bed between the innergate and the Y to the table, a gate dividing the tablesuhstantiallylengthwise, a gate at the end of the defiectors ada ted tobe adjusted to Acontact with the' mes 1, and retarders extending fromthe outer gate across the deflectors to near the inner gate to directthe movement Aot the gangue on the bed into the space between the endsof' the retarders and the inner gate.

1G. In a dry ore separator, a table provided with a mesh, ore detlectorsupon the tahle diagonally dls osed to the length of the table, gangue deectors set upon the ore deflectors at an angle thereto and at an angle,to the length of thevtable, means -for im- )arting motion to the table,means for forcing a current of air through the mesh on the table, aplurality of gates set upon the ore defiectors at an angle thereto, agate set at an end of the ore deflectors and at an angle thereto forforming an ore concentrating gangue de ect-,ors upon the ore detiectorsand at an angle thereto and'at an an le to the length O'thei'able, agate upon't e ore de.

tiectors at an angle thereto an@ disposed lengthwise of the table,rmeans for adjusting the gate upward and downward, a gate at the end ofthe ore deilectors, and means for adjustin the gate to contact .with themesh on the' ied for retarding and arrest'no the movement of the masstobe separated between the gates to form an ore conceutratstant currentof air through the mesh, means for ilnpartin a reciprocating motion tothe table, ore de ectors upon the mesh set at an angle to the length ofthe table, a gate di viding the -table substantially lengthwise near themiddle, gangue detlectors set upon the orexdeflectors and at an anglethereto and at an angle to the length of tne bed on one side 0f thedividing gate, means for forming :fn independent ore concentrating bedon the opposite side of the gate, and means fordecreasing .the rate ofspeed of the upper portion of the mass over the'ore concentratinr bed.

19. In'a dai-y ore separator, a table provided with a mesh, means for i'n' ing a constant current of air up through the mesh, means forimparting motion to the table, ore

deflectors upon the mesh set at au angle t;

the length of the table, gangue deflectors set upon the ore defiectorsat an angle there1 -to and at an angle to the length of` the tableadapted to force the greater part of the gan fue vfrom otfthe ore uponone division of tie table, a gate dividing the table sub' stantiallylengthwise and adapted tobe adA justed vertically', means for arrestingthe movement of the mass to form a concentrating b ed on anotherdivision of the table, and means for directing the movement of thegangue from oti the separated ore.

20.1In a dry-ore separator, a table suspended at an incline bothlaterally and longitudinally and provided with a mesh thereon` means forimparting motion to th'e table` means 'for forcing` air through themesh, a plurality1 et gates adapted to be adjusted upward and downwarddividing the table subst antiaily lengthwise near the center, meansincluding ore and gangue deiectors set at an angle to the motion of thetable and at an angle to each other for forcing )art of the A anguefrom` off the ore on one division of t e table, meansfor forming' an oreconcentrating' bed on the other division of the table including a gateat the end ot' the ore detlectors and retarders set over the oredeflectors and at an angle thereto.

21. In a dry ore separator, an air box, grate bars above the air box, 'amesh upon the grate bars, a mesh beneath the grate bars yin the, airbox, means for forcing the air through the mesh above and below thegrate bars, means "for imparting motion to the table, a gate fordividing the table longitudinally, means for removing part of the gangueon one division of the table, and means for formlng an ore concentratinghedon the other division of the table.

22. In a dry ore separator, an air box, a'

'i U motion to the table, agate dividing the n table substantiallylengthwise, .means for adjusting the gate, means including ore andgangue deectorsvvset atrvanfangle to each otherand to the' motion'of thetable vupon one division of the table for .partially separating thegangue from oft the ore, 'and means including an adjustable gate, oredeiiectors and retarders for forming and maintaining an oreconcentrating bed at a predetermined thickness on the otherdivision ofthe table.

23. In a dryore separator, a table provided with a mesh, means forforcing a constant current of air through the mesh, means for impartingmotion to the table, an adjustable gate dividing the table longitudinelly, means for forming an ore concentrating bed on one divisori of thetable including :1 gate at the outer side of the ore concentraing bedand means for forming a runf way at one side of said bed for conveyingthe gangue from oit the, oreconcentrating 24. in a dry ore separator, atable pli'ovided with a mesh, means for forcing a con stant current ofair through themesh, means for'imparting motion to the table, anadjustable gate for dividing the table longiim the om, an @,jusiable gg@disp-fsw? lengthwise @mess th Lbke vdinghe faafu, gamglze deecors n @nedivision .ar me tubi@ fof Partialy swarming he? ganan@ from o me ore,and means on ma 0% er' division of tha table incurng amd we de fie-etersand :un adjusbe gate at she @ad @f the @re deectors for fmfmmg andmjainin presence @if two wtnessas. WLLMl/ W. BUNSN. I Wlnesses: M. M.GABY, I E, M. www.

